diff options
| -rw-r--r-- | drivers/i2c/busses/i2c-mlxcpld.c | 63 |
1 files changed, 62 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-mlxcpld.c b/drivers/i2c/busses/i2c-mlxcpld.c index 9e45214d1eb6..4e0b7c2882ce 100644 --- a/drivers/i2c/busses/i2c-mlxcpld.c +++ b/drivers/i2c/busses/i2c-mlxcpld.c @@ -11,7 +11,9 @@ #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> +#include <linux/platform_data/mlxreg.h> #include <linux/platform_device.h> +#include <linux/regmap.h> /* General defines */ #define MLXPLAT_CPLD_LPC_I2C_BASE_ADDR 0x2000 @@ -46,6 +48,16 @@ #define MLXCPLD_LPCI2C_ACK_IND 1 #define MLXCPLD_LPCI2C_NACK_IND 2 +#define MLXCPLD_I2C_FREQ_1000KHZ_SET 0x04 +#define MLXCPLD_I2C_FREQ_400KHZ_SET 0x0f +#define MLXCPLD_I2C_FREQ_100KHZ_SET 0x42 + +enum mlxcpld_i2c_frequency { + MLXCPLD_I2C_FREQ_1000KHZ = 1, + MLXCPLD_I2C_FREQ_400KHZ = 2, + MLXCPLD_I2C_FREQ_100KHZ = 3, +}; + struct mlxcpld_i2c_curr_xfer { u8 cmd; u8 addr_width; @@ -463,8 +475,45 @@ static struct i2c_adapter mlxcpld_i2c_adapter = { .nr = MLXCPLD_I2C_BUS_NUM, }; +static int +mlxcpld_i2c_set_frequency(struct mlxcpld_i2c_priv *priv, + struct mlxreg_core_hotplug_platform_data *pdata) +{ + struct mlxreg_core_item *item = pdata->items; + struct mlxreg_core_data *data; + u32 regval; + u8 freq; + int err; + + if (!item) + return 0; + + /* Read frequency setting. */ + data = item->data; + err = regmap_read(pdata->regmap, data->reg, ®val); + if (err) + return err; + + /* Set frequency only if it is not 100KHz, which is default. */ + switch ((data->reg & data->mask) >> data->bit) { + case MLXCPLD_I2C_FREQ_1000KHZ: + freq = MLXCPLD_I2C_FREQ_1000KHZ_SET; + break; + case MLXCPLD_I2C_FREQ_400KHZ: + freq = MLXCPLD_I2C_FREQ_400KHZ_SET; + break; + default: + return 0; + } + + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_HALF_CYC_REG, &freq, 1); + + return 0; +} + static int mlxcpld_i2c_probe(struct platform_device *pdev) { + struct mlxreg_core_hotplug_platform_data *pdata; struct mlxcpld_i2c_priv *priv; int err; u8 val; @@ -479,6 +528,14 @@ static int mlxcpld_i2c_probe(struct platform_device *pdev) priv->dev = &pdev->dev; priv->base_addr = MLXPLAT_CPLD_LPC_I2C_BASE_ADDR; + /* Set I2C bus frequency if platform data provides this info. */ + pdata = dev_get_platdata(&pdev->dev); + if (pdata) { + err = mlxcpld_i2c_set_frequency(priv, pdata); + if (err) + goto mlxcpld_i2_probe_failed; + } + /* Register with i2c layer */ mlxcpld_i2c_adapter.timeout = usecs_to_jiffies(MLXCPLD_I2C_XFER_TO); /* Read capability register */ @@ -497,8 +554,12 @@ static int mlxcpld_i2c_probe(struct platform_device *pdev) err = i2c_add_numbered_adapter(&priv->adap); if (err) - mutex_destroy(&priv->lock); + goto mlxcpld_i2_probe_failed; + return 0; + +mlxcpld_i2_probe_failed: + mutex_destroy(&priv->lock); return err; } |